A unique 1755 Colombian milled eight escudos coin is expected to exceed $60,000 at Stack's Bowers' January 12 auction in New York.
The machine-milled coin, which features a bust of King Ferdinand VI of Spain, received significant coverage in the press when it was discovered in 2004.
Before a milled four escudos example was found some years earlier, it was thought that the first milled coins in Colombia appeared in 1756.
 The 1755 eight escudos machine-milled coin is the only example known to exist |
There are only five eight escudos pieces from 1755 known to have survived, with four of them produced by hand - making this coin one of a kind.
This absence of other examples can be explained not only by the fact that they were struck in limited quantities, but also that the gold content in later coins was reduced - resulting in earlier specimens being melted down for profit.
A 1773 George III pattern 5 guinea coin carries an identical estimate of $60,000.
 The five guinea was produced as a pattern and never circulated |
The coin was produced as a pattern only - meaning that it was only made to test the design and was never circulated.
The profile of the king is intricately realised, with finely textured detailing on the hair and wreath. The reverse is lightly marked at the top left, but otherwise the guinea is in superb condition.
It sold for $52,800 at Stack's Bowers in 1980, and has not been offered on the market since.
January is shaping up to be a big month for coin sales, with a 1787 Brasher Doubloon expected to make $5m at Heritage Auctions.
We have this proof coin minted during the reign of William IV, son of George III.
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